biology, (ii, b, i, c— h: ii, a— d.) Echin. 37 
6-11. Vacant. 
12. Generative System:—‘pores 5 opening by rupture for ex¬ 
trusion of ripe spermatozoa in Antedon pinnule; Marshall 
(191). 
g. CYST IDE A. 
1. General Account: —Woods (303) pp. 140-143 & 148-150. 
2. Vacant. 
8. Homologies :—Cystidea possibly originated from a series of 
abnormal Cladocrinoid larvae; Jaekel (134) p. 1109.—Homo¬ 
logies of various openings with those of recent forms; Russo 
(245) p. 69. 
1-12. Vacant. 
h. BLASTOIDEA. 
1. General Account:—W oods (303) pp. 143-148. 
2. Vacant. 
3. Homologies :—of spiracles and hydrospires, supposed con¬ 
nection with aquiferous and genital systems; Russo (245) p. 72. 
If. Vacant. 
5. Skeletal Anatomy :—Relations of hydrospires to thecal wall 
in Pentremites conoideus (p. 88, pi. xxix), apparently 8 spiracles 
in Eleutheroer. (p. 92, pi. xxx), oral pyramid in Pentremites 
godoni (p. 89, pi. xxix), oral pyramid in P. konincko/aus (p. 90, 
pi. xxix), triangular column in TncoelocHnus wood/nxani (p. 90, 
pi. xxix); Greene (111). 
6-12. Vacant. 
4 
ii. Variation :— 
a. In form :—Vacant. 
b. In form and surface characters :—With depth in Toxopneustes , 
but general variability in an Astropecten ; Ritter (241).—Plates of 
disc in Opkiosteirci, and generally in Cycethra simplex ; Bell (17).— 
In proportion r : P, and local varr. and other details in spp. of 
Psilcister, Hippasteria , Poraniomorpha , Lasicister’, Grieg (113).— 
Relation of r to P, number of paxillae, groove-papillae, and mesh- 
work of test in Solaster papposus et varr.; Grieg (114). 
c. In colour :—Colour of various spp. from Maidive and Laccadive Is., 
see list under m, a, iii; Bell (19).—In spirit and dry specimens 
from Galapagos, see list under iii, a, iv; Clark (48).—Colour in 
life,—of spp. of Holothuria , Pseudostichopus, Paroriza , Psychropotes , 
Deima, Eolgci, Scotocinassa ; Herouard (127) : of deep-sea Ast .; 
Alcock (5) p. 286 : of spp. of Asterina, Nardoa , Asterias ; 
Doederlein (70): of spp. of Brisinga , Lasicister , Poraniomorpha , 
Ophioscolex , Ophiacantha ; Grieg (113): some spp. of Astroporpa , 
Luidia , Linckia , Echinoneus, and Holothuria ; Verrill (285) 
p. 36: of Pentacr. wyvillethornsoni ; Richard (238) p. 84. 
d. Meristic variation :— 
1. Variation from pentamerous symmetry:—in number of genitals 
in Spatangidae; Checchia( 40 & 41).—Humber of rays in Solaster 
papposus , 8-13; Grieg (114).—Eight rays in Asterias glacialis; 
Delage (65) p. 239.—Seven-rayed Asterias with some rays fused 
laterally making an apparent total of 4; Fortin (81).—Six- 
rayed Pyrina ovulum, with corresponding genital and ocular 
plates; Seguin (257).—Six radials in Pentremites godoni (p. 89, 
pi. xxix), additional but imperfect radial in P. pinformis (p. 89, 
pi. xxix); Greene (111).—Sixth ray in regenerate Taxocr .; 
Springer (266) p. 97.—Four rays,—in ffippasterias ; Pearcey 
